Conversion of covalent to ionic behavior of Fe2O3–CeO2–PbO–B2O3 glasses for ionic and photonic application

Abstract

Iron oxide doped cerium lead borate glasses have been prepared and characterized to investigate the structural, physical and optical studies using XRD, FTIR, density and UV–Visible spectroscopy. IR spectroscopic studies have been employed to explore the role of iron oxide in the structure of the studied glasses. Results obtained from FTIR spectra indicate that Fe2O3 acts as a network modifier by converting three coordinated boron atoms [BO3] to four coordinated boron atoms [BO4]. The effect of transition metal content on the optical properties of the present glass system has been studied from the optical absorption spectra. The optical absorption spectra shows the shifting of band edge towards the higher wavelength and corresponding decrease in the band gap is due to the conversion of Ce3+ ions to Ce4+ ions. The physical properties such as density and molar volume help to evaluate the compact structure of prepared glass samples due to presence of [BO4] groups. This is also confirmed by average boron–boron separation result. The addition of iron oxide increases the ionicity value and corresponding decrease in covalent behavior.